"PICK UP LIVE AMMO," says a stenciled sign on the grounds of the Renton Fish & Game Club, in case you accidentally drop some bullets.

It's just another weekend of fun for a bunch of mostly middle-aged guys with office jobs, and a few women, all packing heat, all dressed up in sometimes quite-elaborate cowboy outfits, and all living out the Old West fantasy.

Call it a kind of stress-reducer.

On this Sunday morning, there is Derek Mirkle, 56, of Hobart, who works in accounts payable at Costco and whose weekdays include staring at computer monitors and doing a lot of paperwork.

Bang!

That would be Mirkle shooting at a metal target using a replica 1875 Smith & Wesson Schofield revolver, a gun that legend has it was a favorite of such types as Buffalo Bill Cody and Frank and Jesse James. That replica goes for $800.

"We grew up watching Roy Rogers on Saturday morning, and 'Rawhide' and 'Gunsmoke' and 'Bonanza,' " he says. "For a day or two, I get to be somebody else. We're just big kids playing cowboys and Indians."

Living out the cowboy dream in this way has become a very organized and very popular hobby since it was dreamed up 30 years ago. Participants shoot at targets in a gun range, but they do so dressed up in costumes, using firearms typical of the Old West, and following a script that could have come out of a Hollywood western.

These days, the Single Action Shooting Society has 89,000 members in the U.S. — with 2,500 in this state. There are 1,100 more members in Canada and 2,100 in other countries, mostly in Europe.

Why the burgeoning interest in Poland or Finland?

Says Harper Creigh, 75, of Cypress, Texas, who created the hobby back in 1981, "The American West is a fantasy the world shares. They're almost more fascinated with it than we are."

Creigh says he wanted a friendlier version of shooting competitions that he felt were too competitive.

In this modern world, no matter what country you live in, the Old West evokes much simpler times, says Creigh.

"The West wasn't like we think it is. It's what we wish it was in our minds — the good guys always win, the women are protected, everybody works hard, nobody lies. It's all so much more mental than just the shooting part," he says.

Bang!

The Renton gun club sits on 40 acres, and in the 6 ½ decades since it's been there, plenty of residential development has surrounded it. Club officials say a lot of the nearby residents are members of the club, so presumably they don't mind the blasting sounds.

The Renton United Cowboy Action Shooters meet here on the first Saturday and Sunday of every month.

On this chilly day, 29 members have shown up, and a couple have brought along portable propane heaters. You can go only so far in replicating the Old West.

"It makes you appreciate what we have today," says Mirkle. "As cold as it is today, you don't want to be sleeping on the ground."

He's come dressed as an 1879 Army cavalry colonel, wearing a replica outer coat with a half-cape ($200 from one of the online shops catering to Old West buffs), plus other accouterments that include a vest ($64), boots ($225), leather gloves ($45) and pistol belt ($84).

One of the rules for participating is you dress up in an Old West costume.

Another is that you "adopt a shooting alias appropriate to a character or profession of the late 19th century, a Hollywood western star, or an appropriate character from fiction."

Mirkle has two aliases — Col. Douglas Cedar and Cedar County sheriff.

With so many members, on the national organization's website you can type in an alias you're thinking of using, to make sure it's not taken.

And no cheating by trying to make "Wyatt Earp" into "Marshal Wyatt Earp!"

Mirkle admits he's spent a lot of money on his hobby.

But other participants simply buy denim clothing that can be found at a farm-supply store.

"You don't need to spend $5,000 to play a cowboy. I don't have a wife to tell me what I can't do," says Mirkle.

On this day, he had brought along two of the replica Smith & Wessons, plus a 12-gauge double-barrel "coach gun" like were used by guards sitting next to the driver of a stagecoach ($400), plus a replica Winchester 1873 lever-action rifle that was part of a line known as "the gun that won the West" ($1,000).

The hobby has become so organized that there is a 27-page "Shooters Handbook" detailing just what kind of replicating is and isn't allowed, and going into such rules as, "Holsters may not depart from the vertical by more than 30 degrees when worn."

The way the events go is that participants split into smaller groups, and go from one target area to another. They huddle and listen as a make-believe scenario is read out, such as one in which the hero, "Hazey Grey," is in a shootout with some miners wanting to rob him. The miners are represented by metal targets.

A participant has his weapons on a table, waits for an electronic beep and begins shooting sequentially at the targets. There is always a "safety officer" standing behind a shooter to make sure nothing goes wrong.

Brian Howard, head of the Renton cowboy shooters, says he can't recall a shooting accident in the group's 20-year history.

The worst injury, says Howard, was when a participant tripped over one of the metal targets and suffered a nasty cut on his leg.

Bang!

Another of the shooters is John Palmer, 61, of Renton, a Boeing engineer.

Palmer hasn't gone bonkers on his costume — black jeans, a long black coat from a Western-wear shop, a black shirt, a cowboy hat he got at Salmon Days in Issaquah.

But in this, his first year playing make-believe cowboy, Palmer has spent some $3,500 on two .357 pistols, a rifle and shotgun.

He talks about the camaraderie he feels hanging out with his fellow make-believe cowboys, who always go out for a lunch after one of the weekend meets.

"It's almost a family," he says.

But there is no denying what brought them here.

Bang!

"It's fun hearing the ring of the target. When you miss it, there is this thud from the dirt," says Palmer. "But when you hit it, the metal sings."

Erik Lacitis: 206-464-2237 or elacitis@seattletimes.com